The above code should switch any traffic on a site to the domain name listed, instead of requiring you to list all of the domain name you wish to redirect to the main domain.
If you parked say..
domain1.com
domain2.com
domain3.com
On the same site, but only wanted domain1.com to actually function (the others being redirected to it), then you would just do:
RewriteCond %{HTTP_HOST} .
RewriteCond %{HTTP_HOST} !^domain1\.com [NC]
RewriteRule (.*)
http://domain1.com/$1 [R=301,L]
If you visited domain2.com it would redirect you to domain1.com (preserving the requested file/page).
Regardless, I'm glad you got it doing what you wanted